Magnetic recording device, especially for a hard disk and its manufacturing process

Inactive Publication Date: 2009-05-14
CENT NAT DE LA RECHERCHE SCI
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0016]The dipolar field generated by the magnetic elements allows to define the memory points without structuring the recording support. The non magnetic decoupling layer avoids an exchange coupling that might produce a duplication of the magnetization of the magnetic elements in the recording support, which allows to modify the information in the recording support while keeping the orientation of the magnetization of the magnetic elements.
[0023]The nonmagnetic regions which separate the magnetic elements can be simple air spaces between the magnetic elements.

Problems solved by technology

Admittedly, fabrication defects are liable to greatly modify the inversion field of the magnetic elements, but it suffices that in all cases it remains greater than the inversion field generated by the write head in the monolayer or multilayer unstructured recording support.

Method used

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  • Magnetic recording device, especially for a hard disk and its manufacturing process
  • Magnetic recording device, especially for a hard disk and its manufacturing process
  • Magnetic recording device, especially for a hard disk and its manufacturing process

Examples

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examples

[0104]The layer 43 and the dots 46 are formed of a stack of Co / Pt bilayers, the number of repetitions of which has been chosen so as to obtain inversion fields for the dots that are greater than that of the continuous storage layer.

[0105]The dots 46 of the structured layer are composed of four successive stacks of an elementary bilayer comprising an elementary layer of 0.6 nm of Co and an elementary layer of 1.8 nm of Pt (i.e. eight layers in all). The separating layer 47 is platinum whose thickness is chosen to optimize the field produced in the layer 43 by the elements 46, for example 2 nm.

[0106]If the continuous layer consists, like the dots of a stack of an elementary bilayer of 0.6 nm of Co and of 1.8 nm of Pt repeated four times, the inversion field of the layer 43 is 0.06 T, and that of the dots is at least equal to 0.4 T, that is to say the inversion field of the dots 46 is at least equal to 7 times the inversion field of the layer 43. It is noted indeed that structuring int...

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Abstract

A magnetic recording device comprising at least one unstructured recording support exhibiting at least one elementary magnetic layer, the recording support having a magnetization perpendicular to the plane of the support characterized in that it comprises magnetic elements having a magnetization perpendicular to the plane of the support and a greater inversion field than the inversion field of the recording support, and which are separated from the recording support by a decoupling layer made of a nonmagnetic material so that the magnetic elements produce a dipolar field in the recording support. The magnetic elements are spaced apart from one another by nonmagnetic regions, each magnetic element defining during a write operation a memory point in the recording support.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application claims priority from U.S. Provisional Application No. 60 / 987,921, filed Nov. 14, 2007.FIELD AND BACKGROUND OF THE INVENTION[0002]The subject of the present invention is a magnetic recording device, in particular for a storage means such as a hard disk and its fabrication process. Perpendicular magnetic recording for which the memory points are recorded in a medium with off-plane magnetization has been identified as a very promising procedure for increasing storage densities (towards ultra-high storage densities) in computer hard disks. This technology has recently been instituted and marketed by the main industrial players in the sector: Seagate, Hitachi, Toshiba, etc.[0003]Various solutions have been envisaged for solving the problem of superparamagnetic instability and attaining ultra-high storage densities, for example 1 Tbit per square inch, i.e. 0.155 Tbits per cm2, this corresponding to a 25 nm×25 nm memory point.[0...

Claims

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Application Information

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IPC IPC(8): G11B11/00B05D5/00
CPCG11B5/66G11B5/855G11B5/82G11B5/676G11B5/678
InventorGAUDIN, GILLES LOUISZERMATTEN, PIERRE-JEANMIRON, IOAN MIHAISCHUHL, ALAIN
OwnerCENT NAT DE LA RECHERCHE SCI